An experimental study on velocity field and turbulence field downstream of a single film-hole jet has been completed by using X probe of hot-wire (DISA55M). A fan-shaped hole with flared angle of 15 deg was adopted in the experiment. Under the influence of jet, the turbulence level is obviously increased ad strong anisotropic turbulence exists in the downstream of the hole. In the regions unaffected by the jet, the turbulence can be still regarded as isotropic. the general eddy-viscosity relationships are adaptable yet for simulating the shear stresses i film cooling flow fields. However, the eddy-viscosityvariation itselfis rather complex in these regions that it requires significant modification i different directions. The quotedcomputaitonal results from 3--D Navier-Stokes equations further substantiate these findings. Compared with experimental data, the calculated results of the standard k-epsilon turbulence model could be successful in internal flow of the hole and downstream of jet with the small streamwise inclined angle. In the case of large streamwise angle, the velocity and film cooling effectiveness were underpredicted with this kind of turbulence model. It might be necessary to introduce a non-isotropic turbulence model in the simulation of film cooling flow fields.
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